iPod turns off every time it connects to wifi
After my update to 8.4 my iPod decided to stop working correctly. Every time it connects to wifi it turns off and restarts itself to the apple icon. I have been trying to restart it but I need wifi to connect to icloud and obviously I can't do that. I tried putting my iPod in reset mode to get rid of the update but the product decided to turn off in the middle of the update. I left it alone until it died, and plugged it back in until it was fully charged and it still happens. I've already tried a new cord. How can I put my iPod back to factory settings without using wifi?
iPod touch, iOS 8.4